Kobo: Hide Non-whitelisted Billing Address Countries

Hide non-whitelisted countries on billing address’ country selection.

/* ==UserStyle==
@name               Kobo: Hide Non-whitelisted Billing Address Countries
@description        Hide non-whitelisted countries on billing address’ country selection.
@author             Jason Kwok
@namespace          https://jasonhk.dev/
@version            1.0.0
@license            MIT
@preprocessor       stylus
@var                text  countries  "Country Codes (Separated with “ ” or “,”)"  "()"
==/UserStyle== */

@-moz-document regexp("https://www.kobo.com/[a-z]{2}/[a-z]{2}/account/paymentinformation/billingaddress"), regexp("https://www.kobo.com/[a-z]{2}/[a-z]{2}/checkout/index/.+")
{
    if countries
    {
        :is(#Input_Country, #Country) > option
        {
            display: none;
        }
        
        for country in countries
        {
            :is(#Input_Country, #Country) > option[value={country}]
            {
                display: initial;
            }
        }
    }
}